Re: [PATCH v2] devcoredump: Send uevent once devcd is ready

[Greg KH]

On Tue, Nov 07, 2023 at 04:33:46PM +0530, Mukesh Ojha wrote:
> dev_coredumpm() creates a devcoredump device and adds it
> to the core kernel framework which eventually end up
> sending uevent to the user space and later creates a
> symbolic link to the failed device. An application
> running in userspace may be interested in this symbolic
> link to get the name of the failed device.
> 
> In a issue scenario, once uevent sent to the user space
> it start reading '/sys/class/devcoredump/devcdX/failing_device'
> to get the actual name of the device which might not been
> created and it is in its path of creation.
> 
> To fix this, suppress sending uevent till the failing device
> symbolic link gets created and send uevent once symbolic
> link is created successfully.
> 
> Fixes: 833c95456a70 ("device coredump: add new device coredump class")
> Signed-off-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
> ---
> Change in v2:
>  - Added Fixes tag as per suggestion from [Johannes]
> 
>  drivers/base/devcoredump.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/base/devcoredump.c b/drivers/base/devcoredump.c
> index 91536ee05f14..7e2d1f0d903a 100644
> --- a/drivers/base/devcoredump.c
> +++ b/drivers/base/devcoredump.c
> @@ -362,6 +362,7 @@ void dev_coredumpm(struct device *dev, struct module *owner,
>  	devcd->devcd_dev.class = &devcd_class;
>  
>  	mutex_lock(&devcd->mutex);
> +	dev_set_uevent_suppress(&devcd->devcd_dev, true);
>  	if (device_add(&devcd->devcd_dev))
>  		goto put_device;
>  
> @@ -376,6 +377,8 @@ void dev_coredumpm(struct device *dev, struct module *owner,
>  		              "devcoredump"))
>  		dev_warn(dev, "devcoredump create_link failed\n");
>  
> +	dev_set_uevent_suppress(&devcd->devcd_dev, false);
> +	kobject_uevent(&devcd->devcd_dev.kobj, KOBJ_ADD);
>  	INIT_DELAYED_WORK(&devcd->del_wk, devcd_del);
>  	schedule_delayed_work(&devcd->del_wk, DEVCD_TIMEOUT);
>  	mutex_unlock(&devcd->mutex);
> -- 
> 2.7.4
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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